Why "Average Rate" / "Total Rate" metric variants are not available via Data Aggregator OpenAPI (OData)

Products

• Network Observability
• CA Performance Management

Issue/Introduction

When building a view or report in Portal, a counter-type metric (e.g., TotalDNSRequests in the dnszonemf / DNS Zone metric family) shows three selectable options:

• The raw as-polled total
• Average Rate
• Total Rate

Querying the same metric via the Data Aggregator OpenAPI (OData) returns only the raw as-polled value (e.g., im_TotalDNSRequests). Searching the Vendor Certification (VC) or the metric family (MF) definition for "Average Rate" or "Total Rate" finds nothing — they aren't defined there.

Environment

DX NetOps Performance Management (Data Aggregator, Portal) — all Metric Families with counter-type metrics

Cause

Average Rate and Total Rate are not separate stored metrics. They are computed on the fly, at query time, for any metric whose rollup strategy is Sum (i.e., any counter-type metric) — this is generic behavior across all metric families, not something specific to DNS Zone or any other individual MF. A metric qualifies automatically; nothing needs to explicitly declare rate support in its MF or VC.

The calculation is:

• Total Rate = sum(value) / duration
• Average Rate = average(value / duration) across the samples in the reporting window

(duration = the sample's poll/collection interval.)

Because these values are generated per-query and never written to a persisted table, there is nothing for the OData interface to expose — OData serves stored data only.

Resolution

There is no supported OData query or parameter that returns the Average Rate / Total Rate value directly. Note: the OData resolution=RATE option is unrelated despite the similar name — it is a time-granularity setting meaning "raw/as-polled data," not the per-second rate calculation described above. Do not confuse the two.

Workaround

Rate values can be reconstructed client-side from OData data:

1. Query the raw counter metric (e.g., im_TotalDNSRequests) via OData, including each sample's collection interval/duration.
2. Apply the same formula used internally:
• Total Rate: sum(value) / duration
• Average Rate: average(value / duration) across the samples of interest